Varnish Cache is a web application accelerator, that sit in between visors and web server. It caches frequently requested pages and serve them from memory.

Varnish is Open Source software, you can download it from

https://www.varnish-cache.org/

Varnish work as reverse proxy, so you need something like mod_rpaf installed in Apache web server to see real IP of the visitor, if not all you will see is IP of varnish server.

To find version of varnish, run

varnishd -V

To view varnish stats, run

varnishstat

To view varnish logs, run

varnishlog

• Varnish Cache Error: Package: varnish-4.0.1-1.el6.x86_64 (varnish-4.0)
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